US3614172A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Skid control system
Assignee: ZF Active Safety US Inc
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Filing: 1969-02-27
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Granted: 1971-10-19
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Expires: 1989-02-27
Abstract
Abstract A skid control system for a wheeled vehicle varies the braking pressure as a function of slip speed which varies as a function of vehicle deceleration. The deceleration of the vehicle is detected and integrated to produce a signal Vw2 representative of the actual loss of velocity of the vehicle. This signal Vw2 is subtracted from initial vehicle velocity Vw1 to get a signal Vv indicative of instantaneous vehicle velocity. By subtracting instantaneous vehicle velocity Vv from linear wheel velocity Vw the slip speed signal Vs is obtained. The slip speed signal Vs is fed to a difference circuit which produces an output X when Vs exceeds a reference slip signal Vsr which varies as the deceleration. Output signal X causes actuation of a modulator to relieve brake pressure.
Inventors
- 👤 Hugh E Riordan
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 05:03
CPC Classifications
B; B60; B60T; B60T8/00; B60T8/17; B60T8/176; B60T8/1763; B60T8/17633
Claims Analysis
Total Claims: 14
Claim 1
Independent Claim
115 words
A skid control system for a wheeled vehicle having a plurality of wheels and a braking system for effecting braking of the wheels, said skid control system comprising: first means for providing a first signal having a magnitude indicative of the slip between the vehicle and at least one wheel of the vehicle, second means for modulating the braking at least at that one wheel in response to said first signal attaining a selected magnitude indicative of a preselected magnitude of slip, said second means including means for varying the selected magnitude of said first signal at which brake modulation occurs in response to sensed frictional variations between the one wheel and the driving surface.
Claim 2
Dependent Claim
115 words
A skid control system for a wheeled vehicle having a plurality of wheels and a braking system for effecting braking of the wheels, said skid control system comprising: first means for providing a first signal having a magnitude indicative of the slip between the vehicle and at least one wheel of the vehicle, second means for modulating the braking at least at that one wheel in response to said first signal attaining a selected magnitude indicative of a preselected magnitude of slip, said second means including means for varying the selected magnitude of said first signal at which brake modulation occurs in response to sensed frictional variations between the one wheel and the driving surface.
Claim 3
Dependent Claim
57 words
The system of claim 1 with said first means including accelerometer means for providing a second signal indicative of the deceleration of the vehicle, said second means responsive to said second signal for varying the selected magnitude of said first signal at which brake modulation occurs in accordance with variations in the magnitude of said second signal.
Claim 4
Dependent Claim
33 words
The system of claim 2 with said first and second means as responsive to said first and second signals providing brake modulation at lower magnitudes of slip for lower magnitudes of vehicle deceleration.
Claim 5
Dependent Claim
333 words
A skid control system for a wheeled vehicle having a plurality of wheels and a braking system for effecting braking of the wheels, said skid control system comprising: first means for providing a first signal having a magnitude indicative of the slip between the vehicle and at least one wheel of the vehicle, second means for modulating the braking at least at that one wheel in response to said first signal attaining a selected magnitude indicative of a preselected magnitude of slip, said second means varying the selected magnitude of said first signal at which brake modulation occurs in response to sensed frictional variations between the one wheel and the driving surface, said first means including accelerometer means for providing a second signal indicative of the deceleration of the vehicle, said second means responsive to said second signal for varying the selected magnitude of said first signal at which brake modulation occurs in accordance with variations in the magnitude of said second signal, said first and second means as responsive to said first and second signals providing brake modulation at lower magnitudes of slip for lower magnitudes of vehicle deceleration, first means further comprising velocity means for providing a third signal having a magnitude varying in accordance with variations in magnitude of the speed of one wheel, integrator means responsive to said second signal for providing a fourth signal representative of the integral of said second signal and hence the integral of vehicle deceleration, sample means responsive to actuation of the brake system and to said third signal for providing a fifth signal having a magnitude indicative of the velocity of the wheel prior to actuation of the brake system, first computer means responsive to said fourth and fifth signals for providing a sixth signal having a magnitude indicative of the instantaneous vehicle velocity, and second computer means responsive to said third and sixth signals for providing a seventh signal having a magnitude indicative of the slip between the vehicle and that wheel.
Claim 6
Dependent Claim
333 words
A skid control system for a wheeled vehicle having a plurality of wheels and a braking system for effecting braking of the wheels, said skid control system comprising: first means for providing a first signal having a magnitude indicative of the slip between the vehicle and at least one wheel of the vehicle, second means for modulating the braking at least at that one wheel in response to said first signal attaining a selected magnitude indicative of a preselected magnitude of slip, said second means varying the selected magnitude of said first signal at which brake modulation occurs in response to sensed frictional variations between the one wheel and the driving surface, said first means including accelerometer means for providing a second signal indicative of the deceleration of the vehicle, said second means responsive to said second signal for varying the selected magnitude of said first signal at which brake modulation occurs in accordance with variations in the magnitude of said second signal, said first and second means as responsive to said first and second signals providing brake modulation at lower magnitudes of slip for lower magnitudes of vehicle deceleration, first means further comprising velocity means for providing a third signal having a magnitude varying in accordance with variations in magnitude of the speed of one wheel, integrator means responsive to said second signal for providing a fourth signal representative of the integral of said second signal and hence the integral of vehicle deceleration, sample means responsive to actuation of the brake system and to said third signal for providing a fifth signal having a magnitude indicative of the velocity of the wheel prior to actuation of the brake system, first computer means responsive to said fourth and fifth signals for providing a sixth signal having a magnitude indicative of the instantaneous vehicle velocity, and second computer means responsive to said third and sixth signals for providing a seventh signal having a magnitude indicative of the slip between the vehicle and that wheel.
Claim 7
Dependent Claim
99 words
The system of claim 4 with said second means comprising reference means for providing a eighth signal having a magnitude indicative of said preselected magnitude of slip at which brake modulation occurs and being varied in magnitude in accordance with variations in magnitude of said second signal, said second means further comprising third computer means responsive to said seventh and eighth signals for providing an output signal in response to the relative magnitudes of said seventh and eighth signals having a predetermined relationship, and modulating means responsive to said output signal for modulating the braking at that one wheel.
Claim 8
Dependent Claim
25 words
The system of claim 5 with said output signal being provided when the magnitude of said seventh signal exceeds the magnitude of said eighth signal.
Claim 9
Dependent Claim
310 words
A skid control system for a wheeled vehicle having a plurality of wheels and a braking system for effecting braking of the wheels, said skid control system comprising: first means for providing a first signal having the magnitude indicative of the slip between the vehicle and at least one wheel of the vehicle, second means for modulating the braking at least at that one wheel in response to said first signal attaining a selected magnitude indicative of a preselected magnitude of slip, said second means varying the selected magnitude of said first signal at which brake modulation occurs in response to sensed frictional variations between the one wheel and the driving surface, said first means including accelerometer means for providing a second signal indicative of the deceleration of the vehicle, said second means responsive to said second signal for varying the selected magnitude of said first signal at which brake modulation occurs in accordance with variations in the magnitude of said second signal, said first and second means as responsive to said first and second signals providing brake modulation at lower magnitudes of slip for lower magnitudes of vehicle deceleration, said first means further comprising velocity means for providing a third signal having a magnitude varying in accordance with variations in magnitude of the speed of the one wheel, integrator means responsive to said second signal for providing a fourth signal representative of the integral of said second signal and hence the integral of vehicle deceleration, sample means responsive to actuation of the brake system and to said third signal for providing a fifth signal having a magnitude indicative of the velocity of the wheel prior to actuation of the brake system, computer means responsive to said third, fourth and fifth signals for providing a slip signal having a magnitude indicative of the slip between the vehicle and that wheel.
Claim 10
Dependent Claim
310 words
A skid control system for a wheeled vehicle having a plurality of wheels and a braking system for effecting braking of the wheels, said skid control system comprising: first means for providing a first signal having the magnitude indicative of the slip between the vehicle and at least one wheel of the vehicle, second means for modulating the braking at least at that one wheel in response to said first signal attaining a selected magnitude indicative of a preselected magnitude of slip, said second means varying the selected magnitude of said first signal at which brake modulation occurs in response to sensed frictional variations between the one wheel and the driving surface, said first means including accelerometer means for providing a second signal indicative of the deceleration of the vehicle, said second means responsive to said second signal for varying the selected magnitude of said first signal at which brake modulation occurs in accordance with variations in the magnitude of said second signal, said first and second means as responsive to said first and second signals providing brake modulation at lower magnitudes of slip for lower magnitudes of vehicle deceleration, said first means further comprising velocity means for providing a third signal having a magnitude varying in accordance with variations in magnitude of the speed of the one wheel, integrator means responsive to said second signal for providing a fourth signal representative of the integral of said second signal and hence the integral of vehicle deceleration, sample means responsive to actuation of the brake system and to said third signal for providing a fifth signal having a magnitude indicative of the velocity of the wheel prior to actuation of the brake system, computer means responsive to said third, fourth and fifth signals for providing a slip signal having a magnitude indicative of the slip between the vehicle and that wheel.
Claim 11
Dependent Claim
94 words
The system of claim 7 with said second means comprising reference means for providing a reference signal having a magnitude indicative Of said preselected magnitude of slip at which brake modulation occurs and being varied in magnitude in accordance with variations in magnitude of said second signal, said computer means responsive to said slip and reference signals for providing an output signal in response to the relative magnitudes of said slip and reference signals having a predetermined relationship, and modulating means responsive to said output signal for modulating the braking at that one wheel.
Claim 12
Dependent Claim
25 words
The system of claim 8 with said output signal being provided when the magnitude of said slip signal exceeds the magnitude of said reference signal.
Claim 13
Dependent Claim
354 words
A skid control system for a wheeled vehicle having a plurality of wheels and a braking system for effecting braking of the wheels, said skid control system comprising: first means for providing a first signal having a magnitude indicative of the slip between the vehicle and at least one wheel of the vehicle, second means for modulating the braking at least at that one wheel in response to said first signal attaining a selected magnitude indicative of a preselected magnitude of slip, said second means varying the selected magnitude of said first signal at which brake modulation occurs in response to sensed frictional variations between the one wheel and the driving surface, said first means including accelerometer means for providing a second signal indicative of the deceleration of the vehicle, said second means responsive to said second signal for varying the selected magnitude of said first signal at which brake modulation occurs in accordance with variations in the magnitude of said second signal, said first and second means as responsive to said first and second signals providing brake modulation at lower magnitudes of slip for lower magnitudes of vehicle deceleration, said first means further comprising velocity means for providing a third signal having a magnitude varying in accordance with variations in magnitude of the speed of the one wheel, integrator means responsive to said second signal for providing a fourth signal representative of the integral of said second signal and hence the integral of vehicle deceleration, sample means responsive to actuation of the brake system and to said third signal for providing a fifth signal having a magnitude indicative of the velocity of the wheel prior to actuation of the brake system, reference means providing a reference signal having a magnitude indicative of said preselected magnitude of slip at which brake modulation occurs and being varied in magnitude in accordance with variations in magnitude of said second signal, computer means responsive to said third, fourth, fifth and reference signals having a predetermined relationship for providing an output signal, and modulating means responsive to said output signal for modulating the braking at that one wheel.
Claim 14
Dependent Claim
354 words
A skid control system for a wheeled vehicle having a plurality of wheels and a braking system for effecting braking of the wheels, said skid control system comprising: first means for providing a first signal having a magnitude indicative of the slip between the vehicle and at least one wheel of the vehicle, second means for modulating the braking at least at that one wheel in response to said first signal attaining a selected magnitude indicative of a preselected magnitude of slip, said second means varying the selected magnitude of said first signal at which brake modulation occurs in response to sensed frictional variations between the one wheel and the driving surface, said first means including accelerometer means for providing a second signal indicative of the deceleration of the vehicle, said second means responsive to said second signal for varying the selected magnitude of said first signal at which brake modulation occurs in accordance with variations in the magnitude of said second signal, said first and second means as responsive to said first and second signals providing brake modulation at lower magnitudes of slip for lower magnitudes of vehicle deceleration, said first means further comprising velocity means for providing a third signal having a magnitude varying in accordance with variations in magnitude of the speed of the one wheel, integrator means responsive to said second signal for providing a fourth signal representative of the integral of said second signal and hence the integral of vehicle deceleration, sample means responsive to actuation of the brake system and to said third signal for providing a fifth signal having a magnitude indicative of the velocity of the wheel prior to actuation of the brake system, reference means providing a reference signal having a magnitude indicative of said preselected magnitude of slip at which brake modulation occurs and being varied in magnitude in accordance with variations in magnitude of said second signal, computer means responsive to said third, fourth, fifth and reference signals having a predetermined relationship for providing an output signal, and modulating means responsive to said output signal for modulating the braking at that one wheel.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1974-10-18 | 1975-04-19 | 1975-10-19 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1978-10-18 | 1979-04-19 | 1979-10-19 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1982-10-18 | 1983-04-19 | 1983-10-19 | $7700.00 | Window Closed / Lapsed |